function getStyleObject(objectId)
{
  // cross-browser function to get an object's style object given its id
  if(document.getElementById && document.getElementById(objectId))
  {
    // W3C DOM
    return document.getElementById(objectId).style;
  }
  else if(document.all && document.all(objectId))
  {
    // MSIE 4 DOM
    return document.all(objectId).style;
  }
  else if(document.layers && document.layers[objectId])
  {
    // NN 4 DOM.. note: this won't find nested layers
    return document.layers[objectId];
  }
  else
  {
    return false;
  }
} // getStyleObject

function changeObjectVisibility(objectId, newVisibility)
{
  // get a reference to the cross-browser style object and make sure the object exists
  var styleObject = getStyleObject(objectId);
  if(styleObject)
  {
    styleObject.visibility = newVisibility;
    return true;
  }
  else
  {
    // we couldn't find the object, so we can't change its visibility
    return false;
  }
} // changeObjectVisibility

function moveObject(objectId, newXCoordinate, newYCoordinate)
{
  // get a reference to the cross-browser style object and make sure the object exists
  var styleObject = getStyleObject(objectId);

  if(styleObject)
  {
    styleObject.left = newXCoordinate + "px";
    styleObject.top = newYCoordinate + "px";
    return true;
  }
  else
  {
    // we couldn't find the object, so we can't very well move it
    return false;
  }
} // moveObject